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  • Endoplasmic 内振纽体 - 高级

    Endoplasmic reticulum

    Does a cell have its own ER?
    ::细胞有自己的ER吗?

    Yes, but in this case, the ER is not just for emergencies. True, there might be times when the responds to emergency conditions and the functions of the ER may be needed, but usually the cell's ER is involved in normal functions. are also made on the outside of the ER, and this starts a whole process of protein transport, both around the inside of the cell and to the and out.
    ::是的,但在这种情况下,ER不仅仅是针对紧急情况。 诚然,有时可能需要对紧急情况作出反应,并且需要ER的功能,但通常情况下,该细胞的ER也涉及正常的功能。 ER也出现在ER的外部,这开始了一个完整的蛋白质传输过程,包括细胞内部和细胞内外的蛋白质传输过程。

    The Endoplasmic Reticulum
    ::内院性中转体

    The endoplasmic reticulum (ER) (plural, reticular ) is a network of phospholipid membranes that form hollow tubes, flattened sheets, and round sacs. These flattened, hollow folds and sacs are called cisternae . The membrane of the ER is continuous with the outer layer of the nuclear envelope . The ER has two major functions:
    ::内核内核内核内核内核内核内核内核内核内核外层连续的膜。 内核外核内核内核内核内核内核内核内核外层的膜网构成空心管、扁平板和圆孔。 这些平坦的、空心的折叠体和囊状体称为水晶体。 内核内核内核外层的膜是连续的。 内核内核内核内核内核的外层具有两个主要功能 :

    1. Transport : Molecules, such as proteins, can move from place to place inside the ER, much like on an intracellular highway.
      ::迁移:分子,如蛋白质,可以从一个地方移到另一个地方,在ER内,就像在细胞内高速公路上。
    2. Synthesis : that are attached to ER, similar to unattached ribosomes, make proteins. are also produced in the ER.
      ::合成:ER附着的蛋白质,类似于未结扎的血浆,在ER中也产生蛋白质。

    There are two types of endoplasmic reticulum, rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER).
    ::有两种类型的内核内核内核润滑,一种是粗的内核内核润滑,另一种是平滑的内核内核内核润滑。

    • Rough endoplasmic reticulum is studded with ribosomes which gives it a "rough" sandpaper-like appearance. The ribosomes on the RER make proteins that are then transported from the ER in small phospholipid sacs called transport vesicles . The transport vesicles pinch off the ends of the ER. These vesicles can easily shuttle proteins between the ER and the . The RER works with the Golgi apparatus to move new proteins to their proper destinations in the cell or to the cell membrane. Proteins that are made on the RER are inserted directly into the ER and then transported to their various cellular destinations, including the cell membrane.
      ::粗细内分光体的内分泌液被排挤成一团核糖浆,从而形成一种“粗”沙纸般的外观。RER上的血清产生蛋白质,然后从ER运出,这些蛋白质用叫做运输微粒的小型磷素囊从ER运出。输卵囊从ER的尽头抽出。这些微粒可以很容易地在ER和ER之间传递蛋白。RER与Golgi仪器合作,将新的蛋白质移到细胞或细胞膜的适当目的地。RER上生产的蛋白质直接插入ER,然后运到各个细胞的目的地,包括细胞膜。
    • Smooth endoplasmic reticulum does not have any ribosomes attached to it, so it has a smooth appearance. SER has many different functions some of which are: lipid synthesis, metabolism , calcium ion storage, steroid metabolism, and drug detoxification. Smooth endoplasmic reticulum is found in both and plant cells and it serves different functions in each. The SER is made up of tubules and vesicles that branch out to form a network. In some cells, there are dilated areas like the sacs of RER. Smooth endoplasmic reticulum and RER form an interconnected network of membranous cisternae, tubules, and vesicles.
      ::平滑的内核内分泌体没有附着任何血清,因此外观很顺畅。 SER有许多不同的功能,其中包括:脂质合成、新陈代谢、钙离子储存、类固醇代谢和药物解毒。平滑的内分泌体内分泌体在两个细胞和植物细胞中都发现了,每个细胞的功能各不相同。SER由管状和卵囊组成,形成一个网络。在有些细胞中,有诸如RER. 平滑内分泌体和RER 形成一个由中子囊、管状体和囊体组成的相互联系的网络。
    The Endomembrane System
    Image of the nucleus, endoplasmic reticulum, and Golgi apparatus, and how they work together. The process of secretion from endoplasmic reticuli (orange) to Golgi apparatus (pink) is shown.

    Protein Transport
    ::蛋白质运输

    The ER plays a significant role in protein transport. Proteins are transported through the ER and then throughout the cell are marked with a signal sequence. This sequence is usually a short peptide of a few amino acids attached to the N-terminal end of the protein. This short sequence acts as an address "tag," directing the protein to its correct destination in the cell. At this time, the signal sequence is removed. These proteins are packed into transport vesicles and moved along the cytoskeleton toward their destination.
    ::ER在蛋白质迁移中起着重要作用。 蛋白质通过ER运输, 然后在整个细胞中标记一个信号序列。 这个序列通常是连接在蛋白的N终点的几处氨基酸的短颗粒。 这个短序列作为地址“ 标签 ” , 将蛋白质引导到细胞的正确目的地。 目前, 信号序列被移除。 这些蛋白质被包装在运输的输卵管中, 并沿着细胞箱移到目的地 。

    Summary
    ::摘要

    • The endoplasmic reticulum is a network of phospholipid membranes that form hollow tubes, cisternae, and vesicles.
      ::内分光镜性中脊柱是一个由磷素型膜组成的网络,形成空心管、水晶管和卵囊。
    • The ER is involved in the transport of molecules, such as proteins, and the synthesis of proteins and lipids.
      ::ER参与分子(如蛋白质)的运输以及蛋白质和脂质的合成。
    • The ER can be rough, with embedded ribosomes, or smooth, without ribosomes.
      ::ER可以是粗糙的, 内嵌的脊椎, 或光滑的,没有脊椎。

    Review
    ::回顾

    1. What are the main structural and functional differences between rough endoplasmic reticulum and smooth endoplasmic reticulum?
      ::粗细的内核内核内核润滑与平滑的内核内核内核内核之间在结构和功能上的主要区别是什么?